I wish I could say thank you to the midwife who looked after me when I was in labour with my daughter. I remember knowing that if you push too soon, it does damage and I said umpteen times: "I want to push! Can I push? I'm pushing!" Every time she patiently told me it was OK - never once did she say "I just answered that!" Her kindness made a huge difference to me - and of course I cannot find her now, decades later, to say a proper thank you. Is there someone you would like to say 'Thank you' to, but who you've lost touch with, or maybe they have died - but you still feel grateful?
Lack of public toilets in towns.
Passports not in the drawer I always keep them in. Turning the place upside down.